565703 A7 _____B7__ 五、發明説明（/ ) 【產業上之利用領域】 (請先閲讀背面之注意事項再填寫本頁) 本發明是有關G P S接收裝置，尤其是關於藉由以選 擇性地取出來自多數顆衛星所傳送出之G P S信號，使測 量精度提昇之GPS接收裝置。 【先行技術】 作爲車輛、或船舶等之移動體之導航系統，接收由人 造衛星所輸出之電波，依據其所包含之GPS ( Global Positioning System )信號，測定移動體位置之裝置，例如 在曰本特開平4 一 3 2 4 3 8 4號公報中有所揭示。利用 G P S測定位置之G P S接收裝置，是接收來自3顆以上 人造衛星的G P S信號，利用各人造衛星之繞航訊號來計 算距離資料及高度資料，而偵測出移動體的位置。 經濟部智慧財產局員工消費合作社印製 對於GP S天線，是採用長寬2 0〜6 0mm四方之 正方形、或是直徑2 0〜6 0mm之圓盤狀，俗稱爲補片 天線（patch antenna )之平面天線。如此之平面天線，因 爲集積有多數個天線元件，所以在垂直方向上之指向性要 求極高。又，製成以分集（diversity)構成而可獲得良好 的接收狀態。 再者，利用G P S之導航系統，周知當利用接近地平 線之低仰角衛星所傳送出之電波時，由於受到多路徑、或 電離層延遲等之強烈影響，而使得精度下降。相對於此， 上述之平面天線在垂直方向上的指向性高，而於水平方向 的感度較低，所以不易受到多路徑（multipath)或電離層 本紙張尺度適用中國國家標準（CNS ) A4規格(210Χ297公釐） —4 565703 經濟部智慧財產局員工消費合作社印製 A7 _ B7五、發明説明（f ) 之延遲等之影響。 【發明所欲解決之課題】 然而，例如在機車、或砂灘車等，行進中姿勢變化較 大之移動體上，若GP S是採用平面天線，在移動體之姿 勢爲傾斜狀態下，平面天線之高指向性相對於低仰角衛星 所傳送之電波無法發揮作用而造成精度下降。 另一方面，若是採用在姿勢呈傾斜之狀態下亦可偵測 垂直方向電波之無指向性天線時，由於不僅一直保持接收 來自垂直方向之電波，亦接收來自水平方向之電波，所以 會有無論採用哪一種都無法避免精度降低之技術課題。 本發明之目的，就是在解決上述以往技術上之課題， 提供一種以選擇性地僅接收包含高仰角衛星所傳送出之 GPS信號之GPS接收裝置。 【用以解決課題之手段】 爲了達成上述目的，本發明，是針對於接收由複數顆 衛星所傳送出之G P S信號之G P S接收裝置，以具備有 :接收包含G P S信號電波之天線、及依據上述所接收之 G P S信號，求取各衛星仰角之仰角演算手段、及使上述 各衛星之仰角與特定之基準仰角做比較之比較手段；並以 選擇性地僅取出來自仰角較基準仰角還大之衛星所傳送出 的G P S信號，來作爲其特徵。 依據上述特徵，由於能夠以選擇性地僅利用仰角較大 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 565703 A7 B7 五、發明説明（s ) 之衛星所傳送出的G P s信號，所以可以不易受到多路徑 或電離層之延遲等影響，而做出高精度的測量。 (請先閲讀背面之注意事項再填寫本頁) 【發明實施形態】 以下，參照圖面詳細說明本發明。第1圖是藉由裝配 有本發明之GP S接收裝置，而可大幅提高定位精度之鞍 跨型砂灘車之立體圖；藉由大直徑車輪1 0 1、下擋板 1 0 2及四輪驅動機構等之作用而可發揮高爬坡性與越野 性。在本實施形態中，G P S接收裝置之接收天線1，是 從車輛前部之最上部，以朝向天空而立起設置。 如此之移動體，由於在走行時之姿勢變化很大，接收 天線之指向乃因應姿勢變化而有極大之變化，在車體爲較 大傾斜之狀態下，相對於低仰角之衛星接收天線1必須具 備指向性。 第2圖，是本發明之一實施形態中，GP S接收裝置 之主要部份所構成的方塊圖。 接收天線1 ，例如是使用比以往之移動體上所採用之 經濟部智慧財產局員工消費合作社印製 平面上之補片天線有較低指向性之例如螺形天線（helical antenna )，接收來自複數顆GPS衛星所傳送出之GPS 信號。 高頻處理部2，是將包含在接收天線1所接收電波中 之高頻信號降頻至所期望之周波數帶域。A/D轉換部3 ，是將被降頻之類比信號予以A / D轉換。信號處理部4 ，是從上述A / D轉換部3所輸出之數位信號中抽出衛星 本紙張尺度適用中國國家標準（CNS ) A4規格（21〇><297公釐） 565703 A7 經濟部智慧財產局員工消費合作社印製 五、發明説明（4 ) 繞航訊號。 衛星選擇部5，是先從上述衛星繞航訊號中，將所有 的衛星位置資訊抽出。位置演算部6，是使用所抽出之各 衛星位置，計算出本身之臨時現在位置，其次，使用各衛 星之位置資訊與本身之臨時現在位置，求取所有的衛星仰 角。並且，上述衛星選擇部5，是在以衛星繞航訊號所抽 出之所有衛星中，選擇出仰角爲大於一定基準仰角0 ref之 衛星。最後，使用所選擇出之各衛星的位置資訊，使位置 演算部6求出本身之真正現在位置。 位置演算部6，是由上述所選擇出之衛星之衛星繞航 訊號，求取各衛星之位置資訊及時間資訊，計算出以衛星 發射電波之時刻與本身接收到該電波之時刻之差，以及由 偵測出之杜卜勒頻率（Doppler frequency )，計算出各衛 星與G P S接收裝置間之近似距離，並進一步包含本身之 內部時鐘之誤差，藉由演算而計算出作爲未知數之移動體 的3次元位置或2次元位置。 第3圖，是上述衛星選擇部5之機能方塊圖，包含有 :從衛星繞航訊號抽出各衛星S Τ η之位置資訊，演算該 衛星S Τ η之仰角θ η之仰角演算部5 0 1、及產生基準仰 角0 ref之基準仰角產生部5 0 2、及比較上述所演算之各 衛星S Τ η之仰角0 η與基準仰角0 ref之比較部5 0 3、 及依據上述衛星繞航訊號演算仰角0 η超出基準仰角0 ref 之衛星S Τ η之近似距離L η之近似距離演算部5 0 4。 上述位置演算部6，爲選擇性地僅取仰角0 η超出基準仰角 (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) Α4規格（210Χ：297公釐） 7 565703 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明説明u ) 0 ref之衛星S Τ η之資訊。 其次，參照第4圖之流程圖以及上述第3圖之方塊圖 ，說明本實施形態之動作。在本寳施形態中，如第5圖所 示，以能夠接收7個衛星S Τ 1〜S Τ 7之電波者來作說 明。 在步驟S 1 ，是使從最初之衛星S Τ 1所傳送出之衛 星繞航訊號，由上述信號處理部4而被讀入於衛星選擇部 5之仰角演算部5 0 1。在步驟S 2中，將用以識別所有 衛星之變數Ν(在本實施形態N = 1〜7)設爲「1」。再 者，將用以識別被選擇衛星之變數Μ設爲「0」。在步驟 S 3中，在上述仰角演算部5 0 1演算第Ν個（最初爲第 1個）之衛星S Τ 1的仰角0 1。在步驟S 4中，使所演 算出之仰角0 1與基準仰角0 ref，在比較部5 0 3進行比 較。 如第5圖所示，在本實施形態中，由於衛星S Τ 1之 仰角0 1比基準仰角0 ref還小而進入到步驟S 8。在步驟 S 8中，判別此次之衛星S Τ 1是否是最後的衛星S T 7 。在此，由於被判斷還尙有其他衛星，故在步驟S 9將變 數N予以加算後而回到步驟S 3。 於其次之步驟S 3中，在上述仰角演算部5 0 1演算 第2個衛星S T 2之仰角0 2。在步驟S 4中，使所演算 出之仰角0 2與基準仰角0 ref，在比較部5 0 3做比較。 如第5圖所示，在本實施形態中，由於衛星S T 2之 仰角Θ 2比基準仰角0 ref還大，所以在步驟S 5使得上述 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐了 (請先閲讀背面之注意事項再填寫本頁) 565703 Α7 Β7 經濟部智慧財產局員工消費合作社印製 五、發明説明（4 ) 變數Μ被增算（increment)。於步驟S 6中，是在上述近 似距離演算部5 0 4，演算上述第2個衛星之近似距離L η (在此爲衛星S Τ 2之近似距離L 2 )。於步驟S 7中， 使演算結果之近似距離L 2通知位置演算部6而存於記憶 區域A ( Μ )。也就是，使近似距離L 2被記憶在記憶區 域A ( 1 )中。 在步驟S 8中，是判定此次之衛星是否爲最後的衛星 。要是爲其他之衛星，則在步驟S 9中將變數N增算後回 到步驟S 3，爲其他之衛星時則反覆上所述之各處理。 如以上程序，當所有的衛星S Τ 1〜S T 7執行上所 述之各處理，如第5圖所示地，使仰角0 η超過基準仰角 0 ref的所有衛星S Τ 2〜S Τ 5的各近似距離L 2、L 3 、L 4、L 5置入位置演算部6，分別記憶於其記憶區域 A ( 1 ) 、A(2)、A(3)、A(4)。 在步驟S 1 〇中，於位置演算部6，依據已被記憶在 各記憶區域 A ( 1 ) 、A ( 2 ) 、A ( 3 ) 、A ( 4 )之 近似距離與各衛星之位置座標，來演算移動體之位置。 在本實施形態中，爲了修正各衛星之時間與移動體之 時間之偏差所產生的誤差，也就是將時間偏離量作爲未知 數來計算。由於未知數數目是移動體的3次元座標與時間 偏離量總共爲4個，所以使各衛星S Τ η之位置座標爲（ X η、Υ η、Ζ η);移動體之位置座標爲（X ρ、Υ ρ、 ζ ρ);光速爲C ;接收機之時間偏差爲5 t ;而與各衛星 ST η之近似距離爲L η時，可得到下面數式。 (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) Α4規格（210X297公釐） 565703 A7 _________ B7 五、筆明説明（7 ) {(Xp-X1)2+(YP—Y1)2+(Zp—zl)2}1/2 + c · 6t：=Li (請先閱讀背面之注意事項再填寫本頁) {(Xp-X2)2+( Υρ-γ2)2+(Ζρ_Ζ2^2 j x^2 + c ^ 6t=L2 {(Xp-X3)2+(Yp—Y3)2+(Zp—⑽”工/〜。· μ:。 {(Xp-X4)2+(Yp—Y4)2+(Zp—Z4)2}1/2 + c ^=L4 解上述連立方程式，未知量之移動體位置，是以各衛 星爲中心，並以離衛星之距離爲半徑之4個球面上之交點 所求得。 依據本實施形態，由於僅以選擇性地取出仰角較大之 衛星所傳送出的信號來測量移動體之位置，所以不易受到 多路徑或電離層之延遲等影響，而能夠做出高精度測量。 又，在上述實施形態中，雖是有4顆衛星之仰角超過 基準仰角0 ref，但若是5顆以上的衛星其仰角超過基準仰 角0 ref之情形時，若是依據仰角較大的前面4顆衛星之衛 星繞航訊號來求取位置的話，便能夠做更高精度之測量。 經濟部智慧財產局員工消費合作社印製 【發明之效果】 依據本發明，達成有以下之效果。 (1 )由於是以選擇性地僅取出仰角較大之衛星所傳 送出的信號，所以能夠不易受多路徑或電離層之延遲等影 響，而做出高精度的測量。 (2 )當仰角較大之衛星有多數顆存在之情形時，由 於可以採用其中仰角較大的前面複數顆衛星信號，所以會g 本紙張尺度適用中國國家標準（CNS ) A4規格（210 X 297公釐） 10 565703 A7 經濟部智慧財產局員工消費合作社印製 B7五、發明説明（ί ) 夠更加高精度地測量。 (3 )藉由降低天線之指向性，無論移動體之姿勢如 何變化，皆能夠僅選擇性地利用來自仰角較大之衛星所傳 送出之信號。 【圖面之簡單說明】 第1圖是藉由裝配有本發明之GP S接收裝置，可提 高定位精度之鞍跨型砂灘車之立體圖。 第2圖是本發明之一實施形態G P S接收裝置其主要 部份的構成方塊圖。 第3圖是第2圖的衛星選擇部之機能方塊圖。 第4圖是顯示本實施形態之動作流程圖。 第5圖是將本發明之動作以模式來表現之圖示。 【符號說明】 1 :接收天線 2 :高頻處理部 3 : A / D轉換部 4 :信號處理部 5 :衛星選擇部 6 :位置演算部 (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（ 210X297公釐）"n565703 A7 _____B7__ V. Description of the invention (/) [Application fields in the industry] (Please read the precautions on the back before filling out this page) The present invention relates to GPS receivers, and in particular, to selectively remove The GPS signal transmitted by a satellite makes the GPS receiving device with improved measurement accuracy. [Advanced technology] A navigation system that is a mobile object such as a vehicle or a ship. It is a device that receives the radio waves output by artificial satellites and measures the position of a mobile object based on the GPS (Global Positioning System) signals it contains. It is disclosed in Japanese Patent Application Laid-Open No. 4-1 3 2 4 3 8 4. The GPS receiver, which uses GPS to determine the position, receives GPS signals from more than 3 artificial satellites, and uses the detour signals of each satellite to calculate distance data and altitude data to detect the position of the moving body. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the GP S antenna is a square with a length and width of 20 to 60 mm, or a disc shape with a diameter of 20 to 60 mm. It is commonly known as a patch antenna. Antenna. Since such a planar antenna has a large number of antenna elements integrated, the directivity requirement in the vertical direction is extremely high. In addition, it is constituted by diversity to obtain a good reception state. Furthermore, using the GPS navigation system, it is well known that when radio waves transmitted from low-elevation satellites close to the horizon are strongly affected by multipath or ionospheric delay, the accuracy is reduced. In contrast, the above-mentioned planar antenna has high directivity in the vertical direction and low sensitivity in the horizontal direction, so it is not susceptible to multipath or ionosphere. This paper applies the Chinese National Standard (CNS) A4 specification (210 × 297). (Mm) — 4 565703 Printed by A7 _ B7 of the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. The effect of the delay in the invention description (f). [Problems to be Solved by the Invention] However, for a locomotive or a sand car, etc., on a moving body that has a large change in posture during travel, if the GP S uses a planar antenna, the plane is flat when the posture of the moving body is inclined. The high directivity of the antenna is inferior to the radio waves transmitted by satellites at low elevation angles, resulting in a decrease in accuracy. On the other hand, if a non-directional antenna that can detect vertical radio waves when the posture is tilted is used, it will not only keep receiving the radio waves from the vertical direction, but also the radio waves from the horizontal direction. It is impossible to avoid any technical problem that the accuracy is reduced. An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide a GPS receiving device for selectively receiving only a GPS signal transmitted by a satellite having a high elevation angle. [Means to solve the problem] In order to achieve the above-mentioned object, the present invention is directed to a GPS receiving device that receives GPS signals transmitted by a plurality of satellites, and includes: an antenna for receiving radio waves including GPS signals; The received GPS signals are used to calculate the elevation angle calculation method of each satellite's elevation angle, and a comparison method to compare the elevation angle of each satellite with a specific reference elevation angle; and selectively only take out satellites whose elevation angle is larger than the reference elevation angle. The transmitted GPS signal is used as a feature. According to the above characteristics, because it can selectively use only a large elevation angle (please read the precautions on the back before filling this page) This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 565703 A7 B7 V. Description of the Invention The GP s signal transmitted by the satellite of (s) can not be easily affected by multipath or ionospheric delay, and can make high-precision measurements. (Please read the precautions on the back before filling out this page) [Invention Modes] Hereinafter, the present invention will be described in detail with reference to the drawings. Figure 1 is a perspective view of a saddle-sand sand beach vehicle that can greatly improve positioning accuracy by being equipped with the GP S receiving device of the present invention; with large-diameter wheels 101, lower bezel 102, and four-wheel drive The mechanism can play high climbing and off-road performance. In this embodiment, the receiving antenna 1 of the GPS receiver is set up from the uppermost part of the front of the vehicle so as to face the sky. In such a mobile body, the posture of the receiving antenna changes greatly when traveling, and the direction of the receiving antenna changes greatly in response to the change in posture. In a state where the vehicle body is tilted relatively, it must be compared with the satellite receiving antenna 1 at a low elevation angle. Be directional. Fig. 2 is a block diagram of a main part of a GPS receiver in an embodiment of the present invention. The receiving antenna 1 is, for example, a helical antenna with a lower directivity than a patch antenna printed on a plane printed by a consumer cooperative in the Intellectual Property Bureau of the Ministry of Economic Affairs, which is used on a mobile object in the past. GPS signal transmitted by a GPS satellite. The high-frequency processing unit 2 reduces the high-frequency signal included in the radio wave received by the receiving antenna 1 to a desired frequency band. The A / D conversion section 3 A / D converts the analog signal that has been down-converted. The signal processing unit 4 is to extract satellites from the digital signals output by the A / D conversion unit 3 above. The paper size applies the Chinese National Standard (CNS) A4 specification (21〇 > < 297 mm). 565703 A7 Wisdom of the Ministry of Economic Affairs Printed by the Consumer Cooperative of the Property Bureau V. Invention Description (4) Detour signal. The satellite selection unit 5 first extracts all satellite position information from the satellite detour signals. The position calculation unit 6 calculates its own temporary present position by using the extracted satellite positions, and then uses the position information of each satellite and its temporary present position to obtain all satellite elevation angles. The satellite selection unit 5 selects satellites whose elevation angle is greater than a certain reference elevation angle 0 ref among all the satellites extracted by the satellite detour signal. Finally, using the position information of the selected satellites, the position calculation unit 6 obtains its true current position. The position calculation unit 6 obtains the position information and time information of each satellite from the satellite detour signal of the selected satellite, and calculates the difference between the time when the satellite transmits the radio wave and the time when the radio wave is received by itself, and From the detected Doppler frequency, calculate the approximate distance between each satellite and the GPS receiver, and further include the error of its own internal clock, and calculate the 3 as an unknown moving body by calculation. Dimensional position or 2D position. FIG. 3 is a functional block diagram of the satellite selection unit 5 described above, including: extracting the position information of each satellite S T η from the satellite detour signal, and calculating the elevation angle calculation unit θ η of the satellite S T η 5 0 1 And a reference elevation angle generating unit 5 0 which generates a reference elevation angle 0 ref 2 and a comparison unit 5 0 which compares the calculated elevation angles of each satellite S T η with the reference elevation angle 0 ref 3 and a satellite detour signal based on the above The approximate distance calculating unit 504 that calculates the approximate distance L η of the satellite S τ η that exceeds the reference elevation angle 0 ref of the reference elevation angle η. The above position calculation section 6 is to selectively take only the elevation angle 0 η beyond the reference elevation angle (please read the precautions on the back before filling this page) This paper size applies the Chinese National Standard (CNS) A4 specification (210 ×: 297 mm) 7 565703 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention u) 0 ref of the satellite S T η information. Next, the operation of this embodiment will be described with reference to the flowchart in FIG. 4 and the block diagram in FIG. 3. In the form of this treasure, as shown in Fig. 5, a description will be given of a person capable of receiving radio waves of 7 satellites ST1 to ST7. In step S1, the satellite orbiting signal transmitted from the first satellite ST1 is read into the elevation calculation unit 501 of the satellite selection unit 5 by the signal processing unit 4 described above. In step S2, a variable N (N = 1 to 7 in this embodiment) for identifying all satellites is set to "1". Furthermore, the variable M for identifying the selected satellite is set to "0". In step S3, the above-mentioned elevation calculation unit 501 calculates the elevation angle 0 1 of the Nth (first, first) satellite S T 1. In step S4, the calculated elevation angle 0 1 and the reference elevation angle 0 ref are compared in a comparison unit 503. As shown in FIG. 5, in this embodiment, since the elevation angle 0 1 of the satellite ST 1 is smaller than the reference elevation angle 0 ref, the process proceeds to step S 8. In step S8, it is determined whether the current satellite ST1 is the last satellite ST7. Here, since it is determined that there are no other satellites, the variable N is added in step S9, and the process returns to step S3. In the next step S3, the elevation angle calculation unit 501 calculates the elevation angle 02 of the second satellite ST2. In step S4, the calculated elevation angle 0 2 and the reference elevation angle 0 ref are compared in the comparison unit 503. As shown in FIG. 5, in this embodiment, since the elevation angle Θ 2 of the satellite ST 2 is larger than the reference elevation angle 0 ref, the above paper size is adapted to the Chinese National Standard (CNS) A4 specification (210X297) at step S 5. Millimeter (please read the notes on the back before filling this page) 565703 Α7 Β7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs V. Invention Description (4) The variable M is incremented. In step S 6 Is the approximate distance L η of the second satellite (the approximate distance L 2 of the satellite S T 2) is calculated in the approximate distance calculation unit 504. In step S7, the approximate distance of the calculation result is made. L 2 notifies the position calculation unit 6 and stores it in the memory area A (M). That is, the approximate distance L 2 is memorized in the memory area A (1). In step S8, it is determined whether the satellite this time is The last satellite. If it is another satellite, the variable N is incremented in step S 9 and then returns to step S 3. For other satellites, the above-mentioned processes are repeated. As in the above procedure, when all satellites S T 1 to ST 7 perform the processes described above As shown in FIG. 5, the approximate distances L 2, L 3, L 4, and L 5 of all satellites S T 2 to S T 5 whose elevation angle 0 η exceeds the reference elevation angle 0 ref are placed in the position calculation unit 6, respectively. And memorize it in the memory areas A (1), A (2), A (3), A (4). In step S10, in the position calculation unit 6, according to the memory areas A (1) , A (2), A (3), A (4) and the approximate distance of each satellite and the position coordinates of each satellite to calculate the position of the moving body. In this embodiment, in order to modify the time of each satellite and the time of the moving body The error caused by the deviation is calculated by taking the time deviation as the unknown. Since the number of unknowns is the total of the 3D coordinate of the moving body and the time deviation, the position coordinates of each satellite S τ η are (X η , Υ η, Z η); the position of the moving body is (X ρ, Υ ρ, ζ ρ); the speed of light is C; the time deviation of the receiver is 5 t; and the approximate distance from each satellite ST η is L η (Please read the precautions on the back before filling this page) The paper size applies to the Chinese National Standard (CNS ) Α4 specification (210X297 mm) 565703 A7 _________ B7 V. Description of written instructions (7) {(Xp-X1) 2+ (YP—Y1) 2+ (Zp—zl) 2} 1/2 + c · 6t: = Li (Please read the notes on the back before filling this page) {(Xp-X2) 2+ (Υρ-γ2) 2+ (Zρ_Z2 ^ 2 jx ^ 2 + c ^ 6t = L2 {(Xp-X3) 2 + (Yp—Y3) 2+ (Zp—⑽ ”worker / ~. · Μ :. {(Xp-X4) 2+ (Yp-Y4) 2+ (Zp-Z4) 2} 1/2 + c ^ = L4 Solve the simultaneous equations above. The position of the moving body of unknown quantity is centered on each satellite, and Obtained from the intersection of 4 spheres with the distance from the satellite as the radius. According to this embodiment, since the position of a moving body is measured only by selectively taking out signals transmitted from satellites with large elevation angles, it is not easily affected by multipath or ionospheric delay, and can make highly accurate measurements. In the above embodiment, although the elevation angle of 4 satellites exceeds the reference elevation angle of 0 ref, if the elevation angle of 5 or more satellites exceeds the reference elevation angle of 0 ref, if it is based on the first 4 satellites with a larger elevation angle If the satellite orbits the signal to obtain the position, it can make more accurate measurement. Printed by the Consumer Cooperative of Intellectual Property Bureau, Ministry of Economic Affairs [Effects of Invention] According to the present invention, the following effects are achieved. (1) Since only the signals transmitted by satellites with large elevation angles are selectively taken out, it is not easy to be affected by multipath or ionospheric delay, and can make high-precision measurements. (2) When there are many satellites with large elevation angles, the front multiple satellite signals with larger elevation angles can be used, so this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297) (Mm) 10 565703 A7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, B7 V. Description of Invention (ί) It can measure with higher precision. (3) By reducing the directivity of the antenna, no matter how the posture of the moving body changes, it is possible to selectively use only signals transmitted from satellites with large elevation angles. [Brief description of the drawing] Fig. 1 is a perspective view of a saddle-sand sand beach vehicle capable of improving positioning accuracy by being equipped with the GP S receiving device of the present invention. Fig. 2 is a block diagram showing the structure of a main part of a GPS receiver according to an embodiment of the present invention. FIG. 3 is a functional block diagram of the satellite selection section in FIG. 2. Fig. 4 is a flowchart showing the operation of this embodiment. Fig. 5 is a diagram showing the operation of the present invention in a mode. [Symbol description] 1: receiving antenna 2: high-frequency processing section 3: A / D conversion section 4: signal processing section 5: satellite selection section 6: position calculation section (please read the precautions on the back before filling this page) Paper size applies to China National Standard (CNS) A4 (210X297 mm) " n